1. Field of the Invention
The present invention relates to a semiconductor device, an electronic component module including a semiconductor device, and a method for manufacturing a semiconductor device. In particular, the present invention relates to semiconductor element having improved heat dissipation characteristics and that is included in a semiconductor device.
2. Description of the Related Art
For a semiconductor device including a semiconductor element, when heat is produced in the semiconductor element during its operation, it is important to efficiently dissipate the heat in order to prevent the semiconductor element from being degraded or destroyed and to ensure reliability of the semiconductor element. Accordingly, various techniques for improving the heat dissipation characteristics of a semiconductor element are being developed.
A known semiconductor device including a heat dissipating unit is disclosed in, for example, Japanese Unexamined Patent Application Publication No. 2001-284503. Japanese Unexamined Patent Application Publication No. 2001-284503 discloses a configuration in which a heat dissipating unit is arranged relative to a semiconductor element mounted on a principal surface of a wiring board with conductor bumps disposed therebetween. The heat dissipating unit includes a flat-shaped portion and a projection disposed in a central portion of the flat-shaped portion. The semiconductor element includes a through hole arranged in a direction substantially perpendicular to the principal surface. The heat dissipating unit is arranged such that its projection is inserted in the through hole and the flat-shaped portion is arranged along the principal surface of the semiconductor element, and the heat dissipating unit functions so as to dissipate heat of the semiconductor element.
As described above, the configuration described in the Japanese Unexamined Patent Application Publication No. 2001-284503 having favorable heat dissipation characteristics are obtained by providing a portion of the heat dissipating unit, i.e., the projection inside the semiconductor element having heat generation. Unfortunately, the configuration described in Japanese Unexamined Patent Application Publication No. 2001-284503 has the following problems.
First, the semiconductor element includes the through hole arranged such that the projection of the heat dissipating unit can be inserted therein. This through hole portion produces wasted space because circuit elements cannot be arranged in the through hole portion. This makes it difficult to miniaturize the semiconductor element, and correspondingly, makes it difficult to miniaturize the semiconductor device including the semiconductor element.
In addition, manufacturing the heat dissipating unit having the projection is relatively complicated and expensive. In this case, if the size of the projection is reduced to reduce the size of the wasted space in the semiconductor element, highly precise micromachining is required, which further increases the cost of manufacturing. On the other hand, if the size of the projection is increased to avoid an increase in the cost of manufacturing, the wasted space is increased.
It is necessary to insert the projection provided in the heat dissipating unit into the through hole of the semiconductor element when mounting the heat dissipating unit on the semiconductor device. Unfortunately, aligning the projection and the through hole during insertion is relatively complicated, which makes it difficult to improve productivity. In particular, when the heat dissipating unit includes a plurality of projections, because it is necessary to insert the plurality of projections into a plurality of through holes provided in the semiconductor element at the same time, it is even more difficult to align the projections, which results in further degradation in productivity.